The human brain perceives three-dimensional (3-D) images based on the differences in images between the eyes. By using two images of the same scene obtained from slightly different angles, it is possible to triangulate the distance to an object with a high degree of accuracy. Each eye views a slightly different angle of an object seen by the left and right eyes. The use of 3-D imagery allows the viewer to be immersed in another environment and in some cases allows a viewer to view events, such as for example sports events or concerts, from different vantage points.
Some image-capture systems are based on capturing stereoscopic 2-D images. As an example, 3-D images may be constructed using 2-D images captured using a pair of spatially separated parallel cameras. As another example, a single camera may be physically moved to create the spatial offset when capturing the second of the stereoscopic images. In many cases, the image-capture systems are limited to capturing 3-D imagery within a defined angle.
3-D displays often provide the perception of depth to 2-D images by presenting two offset images separately to the left and right eye of the viewer. These 2-D images are then combined in the brain to give the perception of 3-D depth. Other example methods of displaying “offsetting” 2-D images to provide the perception of depth include using chromatically opposite filters (e.g., red and cyan), different polarizations, or shuttering of lenses over the eyes of the viewer.